linux-generic-mainline: update PV to 4.16
linux-generic-mainline: update PV to 4.16

Linux released 4.16, so update PV from 4.15 to 4.16.

Signed-off-by: Anders Roxell <b4e8e89057bc64bc4f9625a4a821c9ac177a7ed2@linaro.org>

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